Re-introduce printers for Node, Position, PositionAnchorType in GTest

Source/core/dom/Node.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004-2011, 2014 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 879 matching lines @@
     DEFINE_TYPE_CASTS(thisType, Node, node, is##thisType(*node), is##thisType(node))
 
 #define DECLARE_NODE_FACTORY(T) \
     static PassRefPtrWillBeRawPtr<T> create(Document&)
 #define DEFINE_NODE_FACTORY(T) \
 PassRefPtrWillBeRawPtr<T> T::create(Document& document) \
 { \
     return adoptRefWillBeNoop(new T(document)); \
 }
 
+// These printers are available only for testing in "webkit_unit_tests", and
+// implemented in "core/testing/CoreTestPrinters.cpp".
+std::ostream& operator<<(std::ostream&, const Node&);
+std::ostream& operator<<(std::ostream&, const Node*);
+
 } // namespace blink
 
 #ifndef NDEBUG
 // Outside the WebCore namespace for ease of invocation from gdb.
 void showNode(const blink::Node*);
 void showTree(const blink::Node*);
 void showNodePath(const blink::Node*);
 #endif
 
 #endif // Node_h